Students in the second grade are introduced to fractions, learn
new math vocabulary terms, build on their knowledge of addition
and subtraction to include adding and subtracting 2 and 3 digit
numbers and work with the metric system as well as the American
system of weights and measures. Students are taught scientific
methodology such as collecting and analyzing data to prove their
answers.
Grade two students are expected to understand the baseten system
of numeration and build on their first grade introduction to place
values and zero as a place holder. They are expected to recognize
and understand the numbers up to 1000 and identify the place values.
Students should be familiar with estimating, renaming and comparisons
of numbers. In second grade a child should be able to take any
number under 1000 and expand it with numbers or words. For instance,
79 = 7 tens + 9 ones or 532 is 5 sets of 100, 3 sets of 10 and
2 units. Students are expected to have competency using the greater
than, less than or equal to symbols. They should also recognize
odd and even numbers and should be able to skip count by 2's,
3's, 5's, 10's, 25's, 50's and 100's to 1000. Counting forward
or backward by 1's or 10's with any starting point less than 1000
is another second grade accomplishment.
In addition and subtraction, students are expected to have the inverse property
rule memorized and should be able to predict that adding results
in a larger sum and subtraction reduces the result. They should
be able to prove their answers using the inverse relationship
between addition and subtraction. They should be able to recognize
multiple strategies for equations such an s modeling, doubling
and separation of units. They learn to choose appropriate strategies
to be able to do the calculations in their heads, if the numbers
allow.
Part/whole relationships are explored further with the introduction
of fractions. Halves, quarters, thirds and other fractions are
recognized as parts of a set and as such, make up the whole. Students
should be able to represent fractions, compare them, make different
representations of the same fraction, and combine different fractions
to make a whole. Second grade students should also be able to
model and solve problems that use addition, subtraction and the
use of recording in fraction form.
The multiplication tables are introduced and the students are
expected to learn the 2's, 5's and 10's up to "times 10." Multiplication
is presented as repeated addition. This readies the student for
the challenges of grade three.
The foundations of measurement introduced in the first grade
are expanded to include the metric system and when to use it versus
the American system. Second graders learn how to mentally divide
an object into equal parts and they also learn if part A is longer
than part B, and part B is longer than part C, then part A is
longer than part C. These more advanced mathematical measuring
concepts and terminology, partitioning and transitivity, and the
use of standard units of measure and the understanding that students
develop which lets them see that the smaller the unit, the more
of them they will need to make up the whole are all lessons in
most second grade math classes. Lessons in measuring time and
the ability to tell time at 5minute intervals are part of the
curriculum competency goals. Students are also given lessons on
counting various coin denominations to add up to a dollar or more
and practice making change.
In geometry, students are using simple figures to create a given
shape, can describe symmetry and congruency and can explain what
happens to two and three dimensional figures when they are cut
an rearranged. The children use these concepts to prepare themselves
for understanding area, proportions and more advanced spatial
reasoning.
